Sole Assembly Formed From Multiple Preforms and Method and Mold for Manufacturing Same

ABSTRACT

An article of footwear includes an upper and a sole assembly positioned beneath the upper. The sole assembly has a vertically extending channel formed in its bottom surface inward of a periphery of the sole assembly, the channel including opposed sidewalls and an end surface. The sole assembly includes a first portion having a first color; and a second portion having a second color that is different than the first color. An interface between the first portion and the second portion is positioned at a central portion of one of the sidewalls of the channel. A method of forming such an article of footwear is also disclosed.

RELATED APPLICATION DATA

This application is a divisional of U.S. patent application Ser. No.14/252,076 filed Apr. 14, 2014 and entitled “Sole Assembly Formed fromMultiple Preforms and Method and Mold for Manufacturing Same.” U.S.patent application Ser. No. 14/252,076 is entirely incorporated hereinby reference.

FIELD

Aspects of this invention relate generally to a sole assembly for anarticle of footwear, and, in particular, to a sole assembly formed fromtwo preforms and a method and mold for manufacturing such a soleassembly.

BACKGROUND

Conventional articles of athletic footwear include two primary elements,an upper and a sole assembly. The upper provides a covering for the footthat comfortably receives and securely positions the foot with respectto the sole assembly. In addition, the upper may have a configurationthat protects the foot and provides ventilation, thereby cooling thefoot and removing perspiration. The sole assembly is secured to a lowerportion of the upper and is generally positioned between the foot andthe ground. In addition to attenuating ground reaction forces, the soleassembly may provide traction, control foot motions (e.g., by resistingover pronation), and impart stability, for example. Accordingly, theupper and the sole assembly operate cooperatively to provide acomfortable structure that is suited for a wide variety of activities,such as walking and running. An insole may be located within the upperand adjacent to a plantar (i.e., lower) surface of the foot to enhancefootwear comfort, and is typically a thin, compressible member.

The sole assembly may incorporate multiple layers. Some footwear includeonly a midsole, while others may also include an outsole secured to abottom surface of the midsole. The midsole, which is conventionallysecured to the upper along the length of the upper, is primarilyresponsible for attenuating ground reaction forces. The midsole may alsoform the ground-contacting element of footwear. In such embodiments, themidsole may include texturing, such as projections and recesses orgrooves, in order to improve traction. The outsole, when present, formsthe ground-contacting element and may be fashioned from a durable,wear-resistant material.

The midsole may be primarily formed from a resilient, polymer foammaterial, such as ethylvinylacetate (EVA), that extends throughout thelength of the footwear. The properties of the polymer foam material inthe midsole are primarily dependent upon factors that include thedimensional configuration of the midsole and the specificcharacteristics of the material selected for the polymer foam, includingthe density of the polymer foam material. By varying these factorsthroughout the midsole, the relative stiffness and degree of groundreaction force attenuation may be altered to meet the specific demandsof the activity for which the footwear is intended to be used. Inaddition to polymer foam materials, conventional midsoles may include,for example, one or more fluid-filled bladders and moderators.

The sole assembly may be formed of multiple portions, with some or allof the portions having different colors. When EVA is formed in a moldassembly the color lines between the different colored portions maybleed, decreasing the aesthetic appeal of the footwear.

It would be desirable to provide a midsole formed from two preforms anda method and mold for manufacturing such a midsole that reduces orovercomes some or all of the difficulties inherent in prior knowndevices. Particular advantages will be apparent to those skilled in theart, that is, those who are knowledgeable or experienced in this fieldof technology, in view of the following disclosure of the invention anddetailed description of certain embodiments.

SUMMARY

The principles of the invention may be used to advantage to provide asole assembly formed of preforms having different colors and a method ofmanufacturing such a sole assembly.

In accordance with a first aspect, a method of manufacturing a midsolefor an article of footwear includes placing a first preform into a firstrecess in a first mold member of a mold assembly. The first mold memberincludes a plurality of projections extending upwardly from a bottomsurface of the first recess, with each projection positioned inwardlyfrom a peripheral edge of the first recess. A second preform is placedon the first preform such that interfaces between a top surface of thefirst preform and a bottom surface of the second preform are positionedadjacent central portions of the projections. The mold assembly isclosed by positioning a second mold member in contact with the firstmold member, with the first and second mold members cooperating todefine a midsole recess. The mold is maintained for a predeterminedperiod of time at a predetermined temperature such that the first andsecond preforms bond together to form a first portion and a secondportion, respectively, of a sole assembly within the midsole recess. Thesole assembly is removed from the mold.

In accordance with another aspect, a method of manufacturing a midsolefor an article of footwear includes placing a first preform into a firstrecess in a first mold member of a mold assembly, with the first preformhaving a first color, the first mold member including a plurality ofprojections extending upwardly from a bottom surface of the firstrecess, and each projection positioned inwardly from a peripheral edgeof the first recess. A plurality of additional preforms are placed onthe first preform such that each interface between a top surface of thefirst preform and a bottom surface of each additional preform ispositioned adjacent a central portion of one of the projections, with atleast some of the additional preforms having a different color than thefirst color. The mold assembly is closed by positioning a second moldmember in contact with the first mold member, with the first and secondmold members cooperating to define a midsole recess. The mold ismaintained for a predetermined period of time at a predeterminedtemperature such that the preforms bond together to form a sole assemblywithin the midsole recess, and the sole assembly is removed from themold.

In accordance with a further aspect, an article of footwear includes anupper and a sole assembly positioned beneath the upper. The soleassembly has a vertically extending channel formed in its bottom surfaceinward of a periphery of the sole assembly, the channel includingopposed sidewalls and an end surface. The sole assembly includes a firstportion having a first color; and a second portion having a second colorthat is different than the first color. An interface between the firstportion and the second portion is positioned at a central portion of oneof the sidewalls of the channel.

By providing a sole assembly formed from multiple preforms and a methodand mold for manufacturing such a sole assembly, footwear with improvedaesthetic appeal can be produced. These and additional features andadvantages disclosed here will be further understood from the followingdetailed disclosure of certain embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of bottom of a sole assembly of an article offootwear formed from preforms.

FIG. 2 is a section view of a portion of the sole assembly of FIG. 1.

FIG. 3 is a section view of a heel portion of the sole assembly of FIG.1.

FIG. 4 is a section view of first and second preforms of the soleassembly of FIG. 1, shown in a mold assembly used to form the soleassembly.

FIG. 5 is a section view of the mold assembly of FIG. 4 after the soleassembly has been formed from the preforms.

FIG. 6 is a section view of the mold assembly of FIG. 4 with alternativeembodiments of the preforms.

The figures referred to above are not drawn necessarily to scale, shouldbe understood to provide a representation of particular embodiments ofthe invention, and are merely conceptual in nature and illustrative ofthe principles involved. Some features of the mold assembly used to forma sole assembly formed of different preforms and related methods ofmanufacture depicted in the drawings have been enlarged or distortedrelative to others to facilitate explanation and understanding. The samereference numbers are used in the drawings for similar or identicalcomponents and features shown in various alternative embodiments. Moldassemblies used for forming midsoles as disclosed herein would haveconfigurations and components determined, in part, by the intendedapplication and environment in which they are used.

DETAILED DESCRIPTION OF CERTAIN PREFERRED EMBODIMENTS

A sole assembly 10 for an article of footwear is depicted in FIG. 1. Itis to be appreciated that in certain embodiments, sole assembly 10 mayserve as a midsole, with an outsole (not shown) being secured to thebottom surface of the midsole. In other embodiments, as illustratedhere, the bottom surface of sole assembly 10 serves as theground-engaging portion (or other contact surface-engaging portion) ofthe article of footwear.

Sole assembly 10 includes a first portion 12 formed of a first materialhaving a first color, and a second portion 14 formed of a secondmaterial having a second color, where the second color is a differentcolor than the first color.

In certain embodiments, the first and second materials may also havedifferent physical properties and, therefore, different performancecharacteristics. For example, the hardness of the various portions maybe different. It is to be appreciated that any of the known physicalproperties or performance characteristics for sole assemblies can bedifferent for the different portions of sole assembly 10, therebyaltering the support, cushioning, load carrying capability, wearcharacteristics, and tread life of sole assembly 10, for example. Othersuitable physical properties or performance characteristics will becomereadily apparent to those skilled in the art, given the benefit of thisdisclosure.

Sole assembly 10 serves to provide shock-attenuation andenergy-absorption for an article of footwear. Sole assembly 10 can beused for any of various articles of casual footwear havingconfigurations suitable, for example, for walking or lounging. Soleassembly 10 may also be included as part of a wide range of athleticfootwear styles, including shoes that are suitable for soccer, running,basketball, baseball, cross-training, football, rugby, tennis, andvolleyball, for example. An individual skilled in the relevant art willappreciate, therefore, that the concepts disclosed herein with regard tosole assembly 10 may be applied to a wide variety of footwear styles, inaddition to the specific styles discussed herein and depicted in theaccompanying figures.

For purposes of reference in the following description, sole assembly 10may be divided into three general regions: a forefoot region 16, amidfoot region 18, and a heel region 20. Regions 16-20 are not intendedto demarcate precise areas of sole assembly 10. Rather, regions 16-20are intended to represent general areas of sole assembly 10 that providea frame of reference during the following discussion. Although regions16-20 apply generally to sole assembly 10, references to regions 16-20also may apply specifically to first portion 12, second portion 14, orindividual components or portions of sole assembly 10.

For purposes of reference, sole assembly 10 includes a medial side 22and an opposite lateral side 24. Lateral side 24 is positioned to extendalong a lateral side of the foot (i.e., the outside) and generallypasses through each of regions 16-20. Similarly, medial side 22 ispositioned to extend along an opposite medial side of the foot (i.e.,the inside) and generally passes through each of regions 16-20.

As noted above, a separate outsole member may be secured to a bottomsurface 26 of sole assembly 10, and serve as the ground-engaging surfaceof the footwear. In other embodiments, bottom surface 26 itself mayserve as the ground-engaging surface of the footwear.

In known fashion, an upper may be secured to the upper surface of soleassembly 10 in order to fully form the footwear. The upper may besecured to sole assembly 10 with an adhesive, or in any other knownfashion. The upper is not shown here as those skilled in the art arewell aware of how an upper is secured to a midsole, and, therefore, sucha drawing is not necessary for an understanding of the invention.

The materials used to form first portion 12 and second portion 14 ofsole assembly 10 may I be injection phylon (Ethylene Vinyl Acetate or“EVA”). The EVA may have a Vinyl Acetate (VA) level betweenapproximately 9% and approximately 40%. Suitable EVA resins includeElvax®, provided by DuPont, and Engage, provided by the Dow ChemicalCompany, for example. In certain embodiments, the EVA may be formed of acombination of high melt index and low melt index material. For example,the EVA may have a melt index between approximately 1 and approximately50.

The EVA may also include various components including a blowing agent.The blowing agent may have a percent weight between approximately 10%and approximately 20%. Suitable blowing agents include azodicarboamide,for example. In certain embodiments, a peroxide-based curing agent, suchas dicumyl peroxide may be used. The amount of curing agent may bebetween approximately 0.6% and approximately 1.5%. The EVA may alsoinclude homogenizing agents, process aids, and waxes. For example, amixture of light aliphatic hydrocarbons such as Struktol® 60NS may beincluded. The EVA may also include other constituents such as a releaseagent (e.g., stearic acid), activators (e.g., zinc oxide), fillers(e.g., magnesium carbonate), pigments, and clays.

Other suitable materials for first portion 12 and second portion 14 willbecome readily apparent to those skilled in the art, given the benefitof this disclosure.

As noted above, first portion 12 is formed of a material having a firstcolor, while second portion 14 is formed of a material formed of asecond color that is different than the first color. First and secondportions 12, 14 may also have different physical properties. Forexample, first and second portions 12, 14 may have different hardnesses,densities, specific gravities, or any other desired physical property.Other suitable physical properties for which the first and secondportions may have different values will become readily apparent to thoseskilled in the art, given the benefit of this disclosure.

As seen in FIGS. 1-3, bottom surface 26 of sole assembly 10 includes aplurality of vertically extending channels 28. Each channel 28 extendsupwardly from its open end at bottom surface 26 with opposing sidewalls30 and an end surface 32, which is seen in FIG. 2 as an upper surface ofchannel 28. The intersecting surfaces or interfaces 34 between firstportion 12 and second portion 14 are positioned along a central portionof sidewall 30, above bottom surface 26 and below end surface 32.

By positioning interfaces 34 along a central portion of sidewalls 30,any bleeding between the two different colors of first portion 12 andsecond portion 14, which can occur during the molding process and canproduce an uneven line along interface 34, is not visible from anexterior of sole assembly 10 when sole assembly 10 is viewed straight onfrom the bottom, along the surfaces of channel 28, as viewed in FIG. 1.One would need to look at sole assembly 10 at an angle and look intochannel 28 to be able to see any variance in the line forming interface34. Thus, the aesthetics of sole assembly 10 are improved by positioninginterfaces 34 along a central portion of sidewalls 30.

It is to be appreciated that channels 28 can have any desired shape, andcan be positioned at any desired location inboard of an externalperiphery 35 of sole assembly 10. In the embodiment illustrated in FIG.1, a plurality of channels 28 are positioned in forefoot region 16 ofsole assembly 10. These channels 28 are substantially S-shaped, beingformed of a compound curve.

Channels 28 can have linear or non-linear shapes. For example, in theembodiment shown in FIG. 1, channels 28 formed in heel region 20 formconcentric circles. In other embodiments, channels 28 could be formed todefine one or more other shapes, such as a grid or array of hexagons,rectangles, or any other polygons or other shapes. Other suitable shapesfor channels 28 will become readily apparent to those skilled in theart, given the benefit of this disclosure.

In certain embodiments, more than two portions can be used to form soleassembly 10, in order to introduce additional colors to sole assembly10. As illustrated in FIGS. 1 and 3, a third portion 36 having a thirdcolor that is different than the first and second colors is seenpositioned in heel region 20 of sole assembly 10. A fourth portion 38,having a fourth color that is different than the first, second, andthird colors, is also seen positioned in heel region 20 of sole assembly10. In the illustrated embodiment, third portion 36 and fourth portion38 are concentric circles. It is to be appreciated that any number ofcolors can be used for different portions of sole assembly 10.

A mold assembly 40 used to form sole assembly 10 is illustrated in FIGS.4-5, and includes a bottom or first portion 42, and a top or secondportion 44. An upper or top surface 46 of a first recess 47 of firstportion 42 and a lower or bottom surface 48 of second portion 44cooperate to define a midsole recess 50. In the illustrated embodiment,first portion 42, which is positioned beneath second portion 44, formsbottom surface 26 of sole assembly 10, while second portion 44 forms atop surface of sole assembly 10. It is to be appreciated that in otherembodiments, first and second portions 42, 44 can have a differentpositional relationship with respect to one another.

First portion 42 includes a plurality of projections 52 that extendupwardly from upper surface 46 and have vertically extending sides orsidewalls 54. As sole assembly 10 is formed in mold assembly 40,projections 52 serve to form the corresponding channels 28 in soleassembly 10 as described in greater detail below.

In one method of forming sole assembly 10 in mold assembly 40, one ormore first preforms 56 and one or more second preforms 58, which havepreviously been formed in known fashion in one or more separate moldassemblies, are positioned in midsole recess 50 of a heated moldassembly 40. As discussed above, in certain embodiments, first andsecond preforms 56, 58 are formed of EVA.

A release agent may be applied to the exposed surface of first andsecond preforms 56, 58 and/or the surfaces of midsole recess 50 of firstportion 42 and second portion 44 of mold assembly 40 in order tofacilitate the separation of sole assembly 10 from mold assembly 40after its formation. The release agent may be a spray release agent orany other suitable release agent. Suitable materials for the releaseagent include, for example, siloxane and water. Other suitable releaseagents will become readily apparent to those skilled in the art, giventhe benefit of this disclosure.

Each first preform 56 is positioned within first recess 47 of midsolerecess 50 on first portion 42 such that its upper or top surface 60 ispositioned adjacent or along a central portion of a correspondingprojection 52. In certain embodiments, top surface 60 is positionedapproximately midway along a height of projection 52.

In certain embodiments, as illustrated in FIG. 4, a plurality ofseparate first preforms 56 are positioned in first recess 47 of firstportion 42, which combine to form first portion 12 of sole assembly 10.In other embodiments, a single first preform 56 could be positioned infirst recess 47 of first portion 42 with a plurality of aperturesextending through first preform 56 through which projections 52 wouldextend.

Each second preform 58 is positioned on top of the first preforms 56such that its lower or bottom surface 62 is also positioned adjacent oralong a central portion of a corresponding projection 52. In certainembodiments, bottom surface 62 is positioned approximately midway alonga height of projection 52.

In certain embodiments, as illustrated in FIG. 4, a single secondpreform 58 is positioned on top of first preforms 56, and includes aplurality of recesses 64 formed on bottom surface 62, each of whichreceives an upper portion of a corresponding projection 52. In otherembodiments, a plurality of second preforms 58 are positioned on top offirst preforms 56, and combine to form second portion 14 of soleassembly 10.

Mold assembly 40 is then closed so that first portion 42 is in contactwith second portion 44, with first and second preforms 56, 58 seatedwithin midsole recess 50. First portion 42 and second portion 44 may behinged together, or they may be separate elements that are suitablyaligned and placed in contact with one another.

Heat is continued to be supplied to mold assembly 40 with first preform56 and second preform 58 contained therein for a predetermined period oftime. In certain embodiments, mold assembly 40 is heated at atemperature of between approximately 170° C. and 180° C. forapproximately 10 minutes, thereby causing first and second preforms 56,58 to partially melt and bond together to form first portion 12 andsecond portion 14, respectively, of sole assembly 10, filling midsolerecess 50 as seen in FIG. 5. The specific temperature and time periodused to form sole assembly 10 in mold assembly 40 can be varied, inknown fashion, depending on the particular EVA used.

After this heating step is complete, mold assembly 40 is opened, andsole assembly 10, formed of first portion 12 and second portion 14,expands in known fashion after it is removed from mold assembly 26. Soleassembly 10 then goes through typical stabilization steps, includingcooling and trimming, as necessary.

The process of bonding within mold assembly 40, and the expansion ofsole assembly 10, can produce bleeding between the different colors offirst portion 12 and second portion 14, which may create an unevenbleeding lines at interface 34, as seen in FIG. 1 and discussed above.By positioning top surface 60 of each first preform 56 and bottomsurface 62 of each second preform 58 along central portions ofprojections 52, the interfaces 34 that are formed in channels 28 areless visible from an exterior of sole assembly 10, thereby improving theaesthetics of the footwear.

As noted above, providing different physical properties for first andsecond preforms 56, 58 and, therefore, first and second portions 12, 14,allows sole assembly 10 to be customized or optimized to provideparticular aesthetic and/or performance characteristics.

Another embodiment is illustrated in FIG. 6. In this embodiment, acompression molding process is used to form sole assembly 10 in moldassembly 40. In this embodiment, first and second preforms 56, 58 arepositioned in first recess 47 of first portion 42 when mold assembly 40is cool. Mold assembly 40 is then closed so that second portion 44 is incontact with first portion 42. In this embodiment, midsole recess 50,and first and second preforms 56, 58 are sized such that first andsecond preforms 56, 58 are compressed when mold assembly 40 is closed.

Mold assembly 40 is then heated for a predetermined period of time. Incertain embodiments, mold assembly 40 is heated at a temperature ofbetween approximately 130° C. and 140° C. for approximately 15 minutes,thereby causing first and second preforms 56, 58 to partially melt andbond together to form first portion 12 and second portion 14,respectively, of sole assembly 10, filling midsole recess 50 as seen inFIG. 5. The specific temperature and time period used to form soleassembly 10 in mold assembly 40 can be varied, in known fashion,depending on the particular EVA used.

While mold assembly 40 is still closed, it is cooled, allowing soleassembly 10 to fully cure and stabilize. This compression moldingprocess provides for sole assembly 10 to have a finished configurationthat has the same dimensions as that of midsole recess 50.

Once sole assembly 10 is completely stabilized and cured, mold assembly40 is opened, and sole assembly is removed from midsole recess 50. Soleassembly 10 may be further finished, such as with trimming.

Thus, while there have been shown, described, and pointed outfundamental novel features of various embodiments, it will be understoodthat various omissions, substitutions, and changes in the form anddetails of the devices illustrated, and in their operation, may be madeby those skilled in the art without departing from the spirit and scopeof the invention. For example, it is expressly intended that allcombinations of those elements and/or steps which perform substantiallythe same function, in substantially the same way, to achieve the sameresults are within the scope of the invention. Substitutions of elementsfrom one described embodiment to another are also fully intended andcontemplated. It is the intention, therefore, to be limited only asindicated by the scope of the claims appended hereto.

What is claimed is:
 1. An article of footwear comprising: an upper; anda sole assembly positioned beneath the upper, having a verticallyextending channel formed in its bottom surface inward of a periphery ofthe sole assembly, the channel including a sidewall, and comprising: afirst portion having a first color; and a second portion having a secondcolor that is different than the first color, wherein an interfacebetween the first portion and the second portion is positioned at acentral portion of the sidewall of the channel.
 2. The article offootwear of claim 1, further comprising at least one additional channelformed in the bottom surface of the sole assembly.
 3. The article offootwear of claim 2, further comprising a third portion having a thirdcolor that is different than the first and second colors, wherein aninterface between the third portion and one of the first and secondportions is positioned at a central portion of the sidewall of one ofthe channels.
 4. The article of footwear of claim 3, further comprisinga fourth portion having a fourth color that is different than the first,second, and third colors, wherein an interface between the fourthportion and one of the first, second, and third portions is positionedat a central portion of the sidewall of one of the channels.
 5. Thearticle of footwear of claim 1, wherein the first and second portionsare formed of EVA.
 6. The article of footwear of claim 1, wherein aphysical property of the first portion is different than a physicalproperty of the second portion.
 7. A sole assembly for an article offootwear, comprising: a first component having a first surface and afirst color; and a second component engaged with the first component andhaving a second surface and a second color that is different than thefirst color, wherein a first channel is defined extending into the soleassembly from a bottom surface of the sole assembly, wherein the firstchannel includes a first sidewall and a first end surface, wherein thefirst channel is spaced completely inward from an outer periphery of thesole assembly, wherein a first interface between the first surface ofthe first component and the second surface of the second component ispositioned at a central portion of the first sidewall of the firstchannel, and wherein the first end surface of the first channel islocated in the second component.
 8. The sole assembly of claim 7,wherein the second surface of the second component is engaged with thefirst surface of the first component by a compression molded bond formedby application of heat to partially melt and bond materials of the firstcomponent and the second component together.
 9. The sole assembly ofclaim 7, wherein the second component is formed of EVA.
 10. The soleassembly of claim 7, wherein the first component is formed of EVA. 11.The sole assembly of claim 7, wherein a density or hardness of the firstcomponent is different than a density or hardness of the secondcomponent.
 12. The sole assembly of claim 7, wherein the first channelis located in one of a heel region or a forefoot region of the soleassembly.
 13. The article of footwear of claim 7, further comprising asecond channel defined extending into the sole assembly from the bottomsurface of the sole assembly, wherein the second channel is separatedfrom the first channel and includes a second sidewall and a second endsurface, wherein the second channel is spaced completely inward from theouter periphery of the sole assembly, wherein a second interface betweenthe first surface of the first component and the second surface of thesecond component is positioned at a central portion of the secondsidewall of the second channel, and wherein the second end surface ofthe second channel is located in the second component.
 14. The soleassembly of claim 13, wherein the first channel and the second channelare located in a forefoot region of the sole assembly.
 15. The soleassembly of claim 7, further comprising a third component having a thirdsurface and a third color that is different than the first color and thesecond color, wherein a second channel is defined extending into thesole assembly from the bottom surface of the sole assembly, wherein thesecond channel includes a second sidewall and a second end surface,wherein the second channel is spaced completely inward from the outerperiphery of the sole assembly, wherein a second interface between thethird surface of the third component and the second surface of thesecond component is positioned at a central portion of the secondsidewall of the second channel, and wherein the second end surface ofthe second channel is located in the second component.
 16. The soleassembly of claim 15, further comprising a fourth component having afourth surface and a fourth color that is different than the firstcolor, the second color, and the third color, wherein a third channel isdefined extending into the sole assembly from the bottom surface of thesole assembly, wherein the third channel includes a third sidewall and athird end surface, wherein the third channel is spaced completely inwardfrom the outer periphery of the sole assembly, wherein a third interfacebetween the fourth surface of the fourth component and the secondsurface of the second component is positioned at a central portion ofthe third sidewall of the third channel, and wherein the third endsurface of the third channel is located in the second component.
 17. Thesole assembly of claim 7, further comprising a third component having athird surface, wherein a second channel is defined extending into thesole assembly from the bottom surface of the sole assembly, wherein thesecond channel includes a second sidewall and a second end surface,wherein the second channel is spaced completely inward from the outerperiphery of the sole assembly, wherein a second interface between thethird surface of the third component and the second surface of thesecond component is positioned at a central portion of the secondsidewall of the second channel, and wherein the second end surface ofthe second channel is located in the second component.
 18. The soleassembly of claim 17, further comprising a fourth component having afourth surface, wherein a third channel is defined extending into thesole assembly from the bottom surface of the sole assembly, wherein thethird channel includes a third sidewall and a third end surface, whereinthe third channel is spaced completely inward from the outer peripheryof the sole assembly, wherein a third interface between the fourthsurface of the fourth component and the second surface of the secondcomponent is positioned at a central portion of the third sidewall ofthe third channel, and wherein the third end surface of the thirdchannel is located in the second component.
 19. The sole assembly ofclaim 18, wherein the first channel is located in a forefoot region ofthe sole assembly, and wherein the second channel and the third channelare located in a heel region of the sole assembly.
 20. A sole assemblyfor an article of footwear, comprising: a first ethyl vinyl acetatemidsole component having a first surface, a first color, and a firstdensity; and a second ethyl vinyl acetate midsole component having asecond surface, a second color that is different than the first color,and a second density that is different than the first density, andwherein the second surface of the second ethyl vinyl acetate midsolecomponent is engaged with the first surface of the first ethyl vinylacetate midsole component by a compression molded bond formed byapplication of heat to partially melt and bond materials of the firstethyl vinyl acetate midsole component and the second ethyl vinyl acetatemidsole component together, wherein a first channel is defined extendinginto the sole assembly from a bottom surface of the sole assembly,wherein the first channel includes a first sidewall and a first endsurface, wherein the first channel is spaced completely inward from anouter periphery of the sole assembly, wherein a first interface betweenthe first surface of the first ethyl vinyl acetate midsole component andthe second surface of the second ethyl vinyl acetate midsole componentis positioned at a central portion of the first sidewall of the firstchannel, and wherein the first end surface of the first channel islocated in the second ethyl vinyl acetate midsole component.